CSS for translated site, jQuery optimization

main.css : adapting CSS for translated site,
main.js : factoring and optimizing,
page.tpl.php : open fb link in new tab,
node--page_descr_gamme.tpl.php : localization using Drupal's t()
function,
node--page_presentation : navigation up link,
page--front.tpl.php : localization
template.php : custom language block theming